field



April 22:15:47. 0. s. FIELD 2,419,444

LIGHT SIGNAL FdR RAILROADS Original Filed Oct. 14, 1940 2 Sheets-Sheet 1 FIG. 1

RES/57oz 3nnentor mgw Gttorneg April 22, 1947. o. s. FIELD LIGHT SIGNAL FOR RAILROADS Original Filed Oct. 14, 1940 2 Sheets-Sheet 2 WW1 V w Il -i. V wil 19/3- (Ittorneg Patented Apr. 22, 1947 UNITED STATES PATENT OFFICE eral Railway Signal Company,

Rochester,

Original application October 14, 1940, Serial No. 361,060. Divided and this application August 21, 1944, Serial No. 550,383

18 Claims.

This invention relates in general to light signals for use on railways, and has more particular reference to a light signal of the searchlight type wherein a spectacle, carrying different colored roundels, is moved with respect to a single light source to display different signal aspects.

This application is a division of my copending application Ser. No. 361,060, filed October 14, 1940, and entitled Light signals for railroads, which has resulted in Patent No. 2,376,534. dated May 22, 1945.

Although the signal forming the subject matter'oi' this invention is in general of the type disclosed in the patent to O. S. Field No. 2,103,251, granted December 28, 1937, and in the patent to 0. S. Field No. 2,097,785, granted November 2, 1937, it is to be considered in the nature of an improvement over such prior art.

oneof the objects of this invention is to provide an improved optical system with adjusting means therefor, whereby to greatly increase the efficiency and uniformtiy of performance of si nals of this type.

Another object of this invention is to so position the spectacle and its colored rounde'ls as to substantially prevent any sunlight or other light, entering the signal, from washing out the color of the roundel then positioned opposite the light source.

Another object of this invention is to provide improved. means for facilitating the removal and the replacement of the operating mechanism, from and into the outer receiving casing, without thereby changing the exact positional relationship oi the various means involved in the ystem.

Further objects, purposes and characteristic features of this invention will appear as the description progresses, reference being made to the accompanying drawings, showing in a wholly diagrammatic manner, and in no Way whatsoever in a limiting sense one embodiment of the pres ent invention. In the drawings- Fig. 1 is a side sectional view of the signal with certain parts shown in elevation.

Fig. 1A- is a. fragmentary sectional view on line IA-JAof Figs. 1 and 13 viewed in thedirection oi the arrows assuming the signal. operating mechanism to be removed from the outer casing.

Fig. 1B is a fragmentary sectional view taken on line IB--|B of Fig. LA also assuming the signal otieraitingmechanism to be removed from the outer casing;

Fig. 1C is a fragmentary sectional view of the lower portion of the plug board and socket board showing the relationship between their surfaces.

Fig. 2 is a sectional view taken on line 2--2 of Fig. 3 viewed in the direction of the arrows.

Fig, 3 is a sectional view taken on line 3- -3 01 Fig. 2 viewed in the direction of the arrows.

Referring now to the drawings, the signal constituting the present invention includes an outer signal casing 00 (see Fig. 1), of general boxlike form and having a rear opening for'receiving a cover 0 which can be securely closed by a heap. The hasp includes a handle I having a pivot at 5' and which is movable over a locking staple 2. This handle operates when in a closed position to move the attached end of a spring 4 beyond the handle pivot 5, while the hook shaped free end 3 engages a fixed pin 6, whereby to hold the cover on the casing by a toggle effect;

The outer casing 00 has an opening at its front upper portion for receiving an outer lens CL of the convex type, and this lens i held in place by a ring I, which is adapted to receive the usual sun visor B. The lower front portion of the outer casing 00 is provided with three symmetrically arranged threaded lugs 9 for receiving threaded studs Ill to the inner ends of which is clamped a plug board PB that comprises the plug member of a quick detachable plug coupler. Two of these studs I pass through their respective slots in the upper outside corners of the plugboard PB (see Figs. 1 and 113), while the third stud 10 passes through a hole in the plug board PB at the center of its lower edge (see Fig. 1C). The position of the inner face of the plug board PB can be accurately adjusted and maintained in position by adjusting the studs 10 in their bosses or lugs 9, and when it is in a proper position the slots in the outer ends of the threaded studs are leaded to prevent tampering.

The lower side of the outer casing is provided with wire'inlet openings ll, closable if not to be used, by caps l2. In the signalillustrated, the various lead-in wires are fastened to a terminal board I3 from which they pass to the outer face of the plug board PB to there be fasten-ed to plug members such as M.

The casing can be mounted in an adjustable manner by means of the threaded rod l5 and ears l6, so as to be tilted in a vertical plane in a manner similar to that disclosed in the Field Patent No. 2,103,251, dated December 28, 1937, if t be a high signal, and as in the Field Patent No. 2,239,316, dated April 22, 1941, if. it be a low signal.

The outer casing with its wire inlet openings and terminal board I 3, adjustably positioned plug board PB, and outer lens OL, is adapted to receive an operating mechanism casing MC constituting contact operating means and a light projecting unit. With this end in view. two stiff, general vertical springs I! are fastened at l8 to a support member 19 which in turn is fastened to the plug board PB (see Fig. 1). These springs H at their upper ends are bent backwardly in a half-loop form, as shown, in a direction toward the rear of the outer casing 00. As seen most clearly in Figs. 1A, 1B and 3, the outer casing 06 on each side at the inner side has fastened to it a guide member GM, fastened by a stud 2| at its rear end (see Fig. 1A), and supported at its forward end by a slot in the plug board PB (see Figs. 1, 1A and 1B). A bent leaf spring 22 is mounted at its forward end, the spring bearing against the outer casing and being fastened to the guide means GM by rivets 23. Considering now the mechanism casing MC, it is seen that this casing has a groove 24 on each side (see Fig. 3), in a position to be received on the guide means GM, and thus be guided into the outer casing. The mechanism casing also has pivoted to it at 25 (see Fig. l), a U-shaped handle H having an ear 26 at each end, carrying a roller 21.

Fastened to the front opening of the mechanism casing is a plate PL of suitable insulating material which is fastened to cover the front of the mechanism casing MC (see Fig. 2). This plate PL in its upper portion is furnished with an opening to receive an inner lens IL of the convex type, held in place by suitable means, as shown in Fig. 2. Extending rearwardly of this inner lens opening and integral with the plate, is an inwardly tapering fluted light conducting hollow cone or lens barrel terminating in a plane inclined to the vertical, at substantially 30, in order to parallel the adjacently located spectacle as will be described below. This hollow cone is of black insulating material integral with the plate PL, and is fluted on its inner surface to prevent the reflection of light entering the signal from some external source, such as the sun, a locomotive headlight, or the like.

The lower portion SE of plate PL (see Figs. 1 and 2) constitutes the socket board of the plug coupler. This socket board SB is furnished with a plurality of sockets 32, receiving spring coupling members I18, for connecting the plug members such as l4, with socket wire connecting means such as 34, whereby to connect the incoming wires with the mechanism in the mechanism casing by means of the detachable plug coupler constituted by this plug board PB carried by the outer casing 0C and the socket board SB carried by the mechanism casing MC. The connecting means in the sockets of the socket board are held in place by a cover plate 35, removably connected to the socket board SE.

The socket board SB on its forward edges has a beveled outline 36 receivable in a complementally beveled depression 31 in the plug board PB (see Figs. 1C and 2). It should be noted that the inner faces of the plug board and socket board do not contact, but are spaced slightly apart due to laterally extending lugs 40, three in number, on the socket board SB, which contact with three inwardly projecting raised pads or portions 4| on the plug board PB, whereby to position the two boards in a vertical plane, regardless of any warping which might occur near the center portion of the board, other purposes to be fully described below. These lugs 40 and raised portions 4! are located adjacent the three points where the adjusting studs ID are attached to the plug board PB, as disclosed in detail in the parent application Ser. No. 361,060, filed October 14, 1940. This makes it so that any coacting forces between the socket board SB and the plug board PB are directly transmitted to the outer casing 00. Also, this arrangement facilitates proper alignment of the mechanism casing MC when an adjustment of the threaded studs 10 is made.

From the above description it follows, that when the mechanism casing MC is to be inserted into the outer casing QC, it is necessary merely to hold it by the aid of the handle H, while it is slid into the outer casing on the guide members GM. With the handle H in a raised position, the rollers 21 pass over the upper ends of the springs I! (see Fig. 1), and when the plug coupler parts have engaged and the beveled portions on the two boards have interengaged, the handle H can be dropped to the position shown in Fig. 1.- In this way, the rollers 21 are forced backwardly against the stiff springs i1, and are received in the upper curved ends of the springs to thereby force the mechanism casing forward so that the plug coupler boards have their lugs and raised pads firmly pressed against each other. With the handle H in its located position, the rollers 21 pass slightly below a horizontal line through the handle pivots 25, whereby a toggle holding effect is produced by the springs.

It is thus seen that the mechanism casing is supported by the two stiff springs l1, and the engaging beveled portions of the plug board and socket board. Furthermore, it is accurately positioned in a vertical plane and at a given distance from the front of the outer casing by the engaging lugs and pads on the plug coupling boards to form a three-point vertical plane support.

The rear upper portion of the mechanism casing MC has a socket 44 for receiving a barrel 45, carrying a light source LS and a reflector Ref (see Fig. 2). The barrel 45 is held in a fixed position by means of a support frame 46 adjustably carried on three studs 4'! threaded into the mechanism casing. The means for holding the barrel within the socket comprises spring clips 48 on frame 46 and slidable ears 49 on the barrel (see Fig. 1), in much the same manner as disclosed in the Field Patent No. 2,097,785, dated November 2, 1937.

The barrel 45 has a flange member 50 (see Fig. 2) with an inwardly turned portion 5i carrying three adjusting screws 52 which press against a protecting ring between them and the reflector so that their adjustment properly positions the reflector Re). The reflector has an opening 53 to receive the light source LS and is supported on a, felt pad 54 of annular form in turn supported on an annular plate spring 55 having inturned teeth 56 which dig into the felt and anchor the felt to the plate spring.

The lamp can be adjusted in the barrel, and with respect to the reflector, by adjusting means 51, in substantially the same manner as disclosed in the patents above referred to. A cover glass 58 is suitably held by a ring 59 for closing this portion of the mechanism casing, even though the reflector barrel be removed.

The lower rear portion of the mechanism casing MC is open, and can be closed by a transparent cover 60 of glass or the like, and held in place by a chin strap 6|, fastened at one end by a stud 82: to the mechanism casing, and removably held in place at its other end by a stud 63, receivable in a slot 64 in the casing, and readily removable by turning nut 65 back on the stud.

Referring now to Fig, l, and considering the adjusting means for the optical system, it is clear that, by means of the studs l in the outer casing, the position of the plug board PB with reference to the outer lens OL can be accurately adjusted. This also accurately adjusts the distance between the outer lens and the inner lens when the two plug coupler boards are in contact through their three-point support.

By adjusting the lamp LS in its barrel by the adjusting means 51 (see Fig. 2) and adjusting the reflector both by rocking it and if necessary by moving it inwardly or outwardly slightly by means of the three adjusting screws 52, the light source can be accurately positioned at one of the foci of the elliptical reflector Ref. This brings the reflected light to a sharp point, and with an optical axis truly perpendicular to the barrel flange 45a. By adjusting the position of the reflector without varying its relation to the light source, this point where the reflected light meets can be accurately positioned on the optical axis, as at the point 66.

Now by means of studs 47, the entire reflector barrel can be moved relatively to the inner lens so that the light spreading out from the point 66 will just fill the entire area of the inner lens and the virtual image of the reflector assembly accurately positioned at the proper focal point of the lens. Further, by means of the adjustment described above, between the inner lens and the outer lens, the light emanating from the inner lens can be arranged to have angles of incidence to the outer lens so as to emerge therefrom in a substantially horizontal beam. These various adj-ustments result in light travel in general along the dashed lines 61A of Fig. 1.

Referring now more specifically to Fig. 2, and consider the spectacle arm 68 which carries at its upper end an elongated spectacle member S carrying different colored roundels, as R, Y and G, to display red, yellow and green indications respectively, when the spectacle is properly positioned with respect to the light source (see Fig. 3) tally rockable axle 61, and is operated, in a manner to be described below, by electromagnetic means. The spectacle arm 68 is channel shaped, or tubular, or other suitable rigid form, and pivotally connected to the axle at its lower end by bolt means 69, and upwardly of its lower end is slidably fastened to an upstanding arm on the axle by bolt means 10, passing through an enlarged hole H in the web portion of the channel, and a snug fitting hole in the arm of the axle, and carrying a spring 12 on the bolt whereby to form a spring pressed slip clutch between the axle and spectacle. This permits a slight amount of overrun on the part of the spectacle with respect to the axle when the spectacle is moved to either extreme position. This construction cushions jars and shocks, and the movement is so slight in extent as to not interfere with the positioning of, the colored roundels to give the proper light indications.

As can be most clearly seen in Fig. 3, the shelf portion 15 carries two electromagnets having coils 90and 9i placed side by side and extending from rear to front of the mechanism casing; Each of these electromagnets is provided with a suitable The spectacle arm 68 is carried on a horizonarmature pivoted at its rear end, and these armatures Y and G of Fig. 3 are connected by suitable mechanism to the spectacle operating arm Ell as disclosed and described in detail in the parent application Ser. No. 361,060, filed October 14, 1940, to effect the operation of the spectacle S to its yellow and green indicating positions from its normally biased red indicating position. Each armature, at its forward end, operates a plurality of contacts as well as operating the spectacle.

More specifically, the two armatures as seen in Fig. 3 can be considered as the yellow armature Y and the green armature G inasmuch as the operation to produce the yellow and green indicatings respectively under proper conditions of energization. Each armature, when the device is deenergized, rests upon an adjustable back stop. Upon the yellow armature Y picking up, the spectacle is moved from its biased red position to its yellow indicating position, and while maintained the yellow armature picks up. If the green relay be energized while the yellow armature Y is picked up, the green relay picks up its armature G and moves the spectacle to its green indicating position. It is arranged, however, that with the yellow relay deenergized, energization of the green relay will not move the spectacle from its red position. The spectacle is biased by its own weight and by the armature weight, to normally assume its red position so as to display the red indication, a shown in Fig. 3.

The spectacle, as can be noted in Fig. 2, has its roundel carrying portion inclined so as to be substantially parallel with the inner open end of the conical fluted lens barrel at an angle of substantially 30 to the vertical. This is an im portant feature for insuring accurate signal indications. With the spectacle at right angles to the light beam, that is, in a vertical plane, direct sunlight entering the signal, and striking the colored roundels, produces a considerable amount of surface reflection, which emerges from the signal as white light and thus washes out the colored light produced, for example, by the light source and passing through the roundel. Since the sunlight is very strong compared to the light source employed in the signal, a small percentage of sunlight emerging as white light may so seriously wash out the color of the emerging beam as to cause a confusing or inaccurate indication. Furthermore, this may occur, when the roundels are at right angles to the optical axis of the signal, whether or not the light source be energized at the time.

However, in accordance with the present invention the colored roundels are located at an angle of substantially 30 to the vertical, so that any light from an external source entering the signal and striking the smooth surface of the colored roundels will be reflected at such angles as to be dissipated within the signal mechanism itself without affecting the indication displayed by the signal. This tilting of the colored roundels has no material effect upon the efficiency of the signal, since a thirty degree angle of incidence is below the critical angle of reflection, and the percentage of reflected light does not materially change between a zero angle of incidence and any other angle of incidence until after the critical angle has been reached. It should be noted that the signal is provided with the sunshade or hood 8 which protects it from the sun while it is high in the sky. so that any light which enters the signal from the sun after it reaches a point in the sky where such light can enter the signal, impinges upon the colored roundel then in the indicating position at such an angle as to be reflected to dissipating portions of the mechanism such as the black fluted inner surface of the cone shaped lens barrel. Also, the movable spectacle has been tilted to give the col ored roundels the angle indicated so that any light from an external source such as a headlight of a locomotive, which would usually be located below the axis of the signal light beam, will also be reflected from the surface of the roundels to the light dissipating portions of the mechanism. This organization considerably improves the uniformity of peformance of signals of this type and prevents the indications from being diluted due to Sunlight or other external light sources.

The inlet wires that energize the light source employed in this signal are connected through an adjustable resistor 42, and are led through the plug coupler to be connected to the light source at 43.

The above rather specific description of a light signal organization constituting the embodiment of the present invention is given solely by the way of example, and is not intended in any manner in a limiting sense. It is to be understood that the various modifications, adaptations and alterations, can be applied to meet the requirements of practice without in any manner departing from the spirit or scope of the invention except as limited by the appended claims.

Having described my invention I now claim:

1. In a light signal of the search light type, an outer casing, an inner mechanism casing receivable in the outer casing, a lens in the outer casing, a lens in the inner casing, means for slidably supportin the inner casing in the outer casing so that the optical axes of the lenses coincide, and adjusting means for limiting the inward sliding movement of said inner casing to provide a predetermined distance measured along their optical axes between the two lenses.

2. In a light signal of the search light type, an outer casing, an inner mechanism casing receivable in the outer casing, a lens in the outer casing, a lens in the inner casing, means for slidably supporting said inner mechanism casing for movement into and out of the outer casing in a direction where the optical axes of said lenses coincide, adjustable means for limiting the inward movement of said inner casing to provide a predetermined distance between said lenses along their optical axes, a barrel insertable in the inner casing in line with the axes of the lenses, a light source and an associated reflector in the barrel, a movable signal spectacle intercepting the axes of the lenses, and means for adjusting the distances between the barrel and the lenses as measured along the optical axes of the lenses.

3. In a light signal of the search light type, an outer casing, an inner mechanism casing receivable in the outer casing, a lens in the outer casing, a lens in the inner casing, fixed guide bars on the inside of the outer casing cooperating with grooves on each side of the inner casing for slidably supporting said inner casing for movement in and out of the outer casing, means including adjustable screws for limiting the inward movement of said inner casin to a position where there is a predetermined distance between said lenses along their optical axes, a barrel insertable in the inner casing in line with the axes of the lenses, a light source and an associated reflector in the barrel, a movable signal spectacle intercepting the axes of the lenses, means for adjusting the distance from the barrel to the lenses as measured along the optical axes of the lenses, adjusting means for varying the position of the reflector in the barrel, and adjusting means for varying the position of the light source in the barrel.

4. In a light signal of the search light type, an outer casing, an inner mechanism casing receivable in the outer casing, a lens in the outer casing, a lens in the inner casing, means for slidably supporting said inner casing for movement into and out of the outer casing and limiting its inward movement to a predetermined adjustable position, a barrel insertable in the inner casing in line with the axes of the lenses, a light source and an associated reflector in the barrel, a movable colored spectacle intercepting the axes of the lenses, means for adjusting the distances of the barrel to the lenses as measured along their optical axes, the spectacle, where it intercepts the axes of the lenses being inclined to the axes at an angle of substantially 60, whereby to prevent light, entering the signal substantially along the axes, from washing out due to surface reflection from the spectacle, the color of light emerging from the signal.

5. In a light signal of the search light type, an outer casing, an inner mechanism casing receivable in the outer casing, a lens in the outer casing, a lens in the inner casing, means for slidably supporting said inner casing to provide for sliding movement into and out of the outer casing in a direction along the optical axes of said lenses, adjustable means for limiting the inward movement of said inner casing to provide a predetermined distance between said lenses, a barrel insertable in the inner casing in line with the axes of the lenses, a light source and an associated reflector in the barrel, a movable colored signal spectacle intercepting the axes of the lenses, means for adjusting the distances of the barrel to the lenses as measured along their optical axes, adjusting means for varying the position of the reflector in the barrel, adjusting means for varying the position of the light source in the barrel, the spectacle, where it intercepts the axes of the lenses being inclined to the axes at an angle of substantially 60, whereby to prevent light which enters the signal substantially along the axes from washing out due to surface reflection on the spectacle, the color of light emerging from the signal.

6. In a color light signal of the search light type, an outer signal casing including a lens. an electrically operable light projecting unit including a lens and a movable color screen and slidable into and out of said casing, a multiple contact plug coupler having its elements secured to said casing and said light projecting unit respectively, said plug coupler being connected and disconnected as said light projecting units is moved into and out of the mechanism casing, and cooperating guiding means associated with the opposite inner surfaces of said casing and corresponding outer surfaces of said light projecting unit for supporting said light projecting unit during its movement into and out of said casing and for aligning said unit in a predetermined relation to said casing.

7. In a light signal of the search light type, an outer signal casing including a lens, an electrically operable signal mechanism having a light projecting unit and a movable spectacle for selecting the color of the light to be projected, a multiple contact plug coupler having its plug and socket elements secured to said casing and said mechanism respectively, said plug coupler being provided to supply detachable electrical connections between said electrically operable mechanism and connections extending from said signal casing, and cooperating guiding means associated with the opposite inner surfaces of said casing and corresponding outer surfaces of said mechanism for supporting said mechanism during its movement into and out of said casing and for aligning the respective elements of said plug coupler.

8. In a color light signal of the search light type, an outer casing including a lens, an electrio'ally operable light projecting unit including a lens and a movable color selecting spectacle, said unit being of suitable size and shape to fit into said casing, a multiple contact plug coupler having its plug and socket elements respectively secured to said casing and said unit, cooperating guiding means associated with the inner surfaces of said casing and corresponding outer surfaces of said light projecting unit for supporting said unit during its movement into and out of said casing and for aligning the optical axes of said lenses and the cooperating portions of said plug coupler, and screw threaded means for adjustably connecting that element of the plug coupier associated with said casing to define the innermost extent of the movement of said light projecting unit into the casing, and thereby provide for the proper relationship between the lenses along their common optical axis.

9. In a light signal of the search light type, an outer casing including a lens, an electrically operable light projecting unit including a lens and a movable color screen, said unit being of such size and shape as to fit into said outer casing, a quick detachable plug coupler having its opposite elements respectively secured to said casing and said unit, cooperating guide means associated with the opposite inner surfaces of said casing and corresponding outer surfaces of said unit for supporting said unit during its movement into and out of said casing and while enclosed in said casing, said guide means also acting to align said lenses on a common optical axis, and spring biasing means associated with said guiding means on said casing so as to limit sidewise displacement of said unit although readily permitting proper positioning of said unit in said casing.

10. In a color light signal of the search light type, a casing including a lens, an electrically operable light projecting unit including a lens and a movable color screen, said unit being slidable into and out of said casing, 51, multiple contact plug coupler having its separable elements secured to said casing and light projecting unit respectively, a guiding device for supporting said unit during its movement into and out of said casing and for aligning said unit in predetermined relationship to said casing, a handle pivotally connected to said light projecting unit and co operating with a yieldable connection secured to said casing to exert spring pressure for holding said unit in its innermost position in the casing when the handle is swung to a particular position.

11. In a color light signal of the search light type, a conical lens barrel having an opening at each end, a projecting lens in the larger end of said barrel, a movable spectacle having a plurality of differently colored roundels, means for operating said spectacle to position any selected one of said roundels opposite the opening at the smaller end of said lens barrel at an inclined angle with respect to the optical axis of said lens and adjacent the focal point of such lens, and a source of light and reflector organization for focusing a beam of light at said focal point of said lens, whereby some of the light impinging upon the surface of a colored roundel from a source of light external to said signal is reflected away from the beam of light produced by said light source so as to prevent the dilution of the color of the light beam projected through the colored roundel then in position opposite the small end of said lens barrel.

12. In a multiple aspect color light signal of the search light type, a hollow conical lens barrel having a lens in the larger end and an opening in the smaller end, a spectacle having a plurality of differently colored roundels, means for moving said spectacle to position said roundels one at a time over the opening in said lens barrel within the optical axis of the lens, each of said roundels being inclined with respect to the optical axis of said lens at an angle to cause external light to be reflected from the outer surface of the roundels in a direction to strike the inner surface of the lens barrel, whereby external light will not be reflected by said roundels along the main beam of the signal to modify the color aspect of the signal.

13. In a light signal of the search light typ a signal mechanism having projecting lens at one end of a hollow light barrel, a light source and an associated reflector at the opposite end of the barrel for concentrating a, beam of light at the focal point of said lens, and a colored roundel adjacent the focal point of said lens for intercepting the beam of light, said colored roundel bei inclined at an angle of substantially with respect to the optical axis of said lens, whereby light entering the signal substantially along said optical axis is prevented from being reflected due to surface reflection from said roundel and thereby prevents the Washing out of the color of light emerging from said signal as produced by said light source and passing through said colored roundel.

14. In a color light signal of the search light type, a hollow conical lens barrel having an opening at each end and the inner surfaces of such barrel being fluted, a projecting lens located in the opening in the larger end of said barrel, 9. colored roundel positioned at the opening in the smaller end of said barrel and inclined at an angle with respect to the optical axis of said lens, said roundel being at an angle to reflect external light against the inner fluted surface of said lens barrel, and a source of light and reflector organization for producing a beam of light passing through said colored roundel and focused at the focal point of said lens, whereby any light entering said lens barrel from an external source is reflected away from the beam of light produced by said light source so as to prevent the dilution of the color of the projecting light beam,

15. In a color light signal of the search light type, a hollow conical lens barrel having an opening at each end and the inner surfaces of said barrel being constructed to absorb light rather than to reflect light, said cone having a radius compared to the length of said cone so as to give a limit angle of spread away from its axis, a projecting lens in the opening at the larger end of said barrel, a movable spectacle having colored roundels positionable at the opening in the smaller end of said barrel and inclined at an angle with respect to the optical axis of said lens such that any light from a source outside said lens impinging upon the surface of any one of said colored roundels along said optical axis will be reflected at an angle away from the optical axis of said lens greater than the angle of spread of said cone, means for moving said spectacle to its difierent positions, a source of light and reflector organization for producing a beam of light passing through a roundel and focused at the focal point of said lens to thereby project a colored light beam, whereby the colored light beam projected by said signal cannot have its color washed out by the reflection of light from an external source from the surface of a roundel.

16. In a light signal of the search light type, a signal mechanism having a light projecting lens at one end of a hollow light barrel, a light source and an associated reflector at the opposite end of the barrel for concentrating a beam of light at the focal point of said lens, a, movable spectacle having a plurality of colored roundels positionable one at a time in the beam of light adjacent said focal point, said spectacle being inclined at an angle of substantially 60 with respect to the optical axis of said lens and said roundels being parallel with said spectacle, and electromagnetic means for operating said movable spectacle to its different positions, whereby light entering the signal substantially along said optical axis is prevented from being reflected from the surface of that colored roundel then positioned in said beam of light to thereby maintain the color of the projected light beam at its proper hue so that it is readily distinguishable from the other colored light beams given by the signal.

17. In a multiple aspect color light signal of the search light type, a signal mechanism having a projecting lens at one end of a hollow lens barrel, a light source and an associated reflector at the opposite end of the barrel for concentrating a beam of light at thefocal point at said lens, a movable spectacle having a plurality of colored roundcls, said roundels being positionable one at a time in said beam of light adjacent said focal point and inclined at an angle with respect to the optical axis of said lens and in such a direction that light impinging upon the surface of a colored roundel from an external source will be reflected away from and above said optical axis, and electromagnetic means for operating said movable spectacle to its different positions. 18. In a color light signal of the search light type an outer casing and an inner mechanism casing slidable into and out of said outer casing, cooperating lenses in each of said casing, a detachable plug coupler having two separable members attached respectively to said inner casing and said outer casing, means associated with that member of said coupler attached to said outer casing for adjusting its position with respect to said outer casing to limit the inward movement of said inner mechanism casing and provide a predetermined selected distance between said lenses along their optical axes, said members of said plug coupler having beveled projecting and matching beveled inset faces, a manually operable lock handle pivoted to each outer side of the inner casing and carrying two rollers, one on each side of the inner casing, and two stiff springs, one for each inner side of the outer casing, each being fixed at one end to its side or the outer casing and cooperating at its other end with a roller on said handle for providing a yieldable means for holding the inner mechanism casing in place within the outer casing.

OSCAR S. FIELD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,239,336 Moore Apr. 22, 1941 2,111,650 Wells et al Mar. 22, 1938 2,230,853 Wells (I) Feb. 4, 1941 2,333,967 Wells (II) Nov. 9, 1943 2,037,650 Field (I) Apr. 14, 1936 2,103,251 Field (II) Dec. 27, 1937 

